Program crash: GC destroys an object unexpectedly

[eugene]

On Thursday, 23 September 2021 at 14:31:34 UTC, jfondren wrote:
> Nice. I thought of GC.addRoot several times but I was 
> distracted by the general solution of using object lifetimes 
> with it, so that a struct's destructor would call 
> GC.removeRoot. For your case just pinning these and forgetting 
> about them is the easiest way to do it.

Yes, these two must live until the end of main().
Moreover, in real (C) programs I (usually) do
not create state machines on the fly,
instead I keep them in pools, like RX/TX machines pools
in echo-server and in echo-client.